Image forming apparatus, method for controlling the same, and recording medium

ABSTRACT

An image forming apparatus includes a detection unit that detects a user of the image forming apparatus, a power supply control unit that, when a person approaching the image forming apparatus is detected by the detection unit when the image forming apparatus is in a power saving state where power supply to a function unit included in the image forming apparatus is stopped, activates the function unit while maintaining the display unit in a non-display state, and a display control unit that, when the user of the image forming apparatus instructs the display unit to present display after power is supplied to the function unit by the power supply control unit, changes the display unit to a display state.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation, and claims the benefit, of U.S.patent application Ser. No. 15/664,421 filed Jul. 31, 2017, which claimsthe benefit of U.S. patent application Ser. No. 14/658,024 filed Mar.13, 2015 (now U.S. Pat. No. 9,746,811), which claims priority toJapanese Patent Application No. 2014-054162 filed Mar. 17, 2014 and toJapanese Patent Application No. 2014-125738 filed Jun. 18, 2014. Each ofU.S. patent application Ser. No. 15/664,421, U.S. patent applicationSer. No. 14/658,024, Japanese Patent Application No. 2014-054162, andJapanese Patent Application No. 2014-125738 is hereby incorporated byreference herein in its entirety.

BACKGROUND Field

Aspects of the present invention are generally related to an imageforming apparatus including a sensor for detecting a person approachingthe image forming apparatus, a method for controlling the image formingapparatus, a program, and a storage medium.

Description of the Related Art

A technique to return an image forming apparatus from a power savingstate when a sensor provided in the image forming apparatus detects aperson approaching the image forming apparatus, is known (refer toJapanese Patent Application Laid-Open No. 2012-203132).

In the technique discussed in the above-described Japanese PatentApplication Laid-Open No. 2012-203132, when a pyroelectric sensordetects a person, a user interface (UI) touch panel lights up. Then,when a user gives instructions to execute a job on the lit-up UI touchpanel, the image forming apparatus warms up and its state transitions toa standby state.

However, in the technique discussed in Japanese Patent ApplicationLaid-Open No. 2012-203132, since the UI touch panel lights up when thesensor detects a person, the UI touch panel may light up even when aperson who is not a user of the image forming apparatus passes in frontof the image forming apparatus.

In the technique discussed in the Japanese Patent Application Laid-OpenNo. 2012-203132, the image forming apparatus does not warm up until theuser gives the instructions to execute a job. More specifically, in thetechnique discussed in Japanese Patent Application Laid-Open No.2012-203132, after giving instructions to execute a job, the user has towait in front of the image forming apparatus until warm-up of the imageforming apparatus is completed.

SUMMARY

Aspects of the present invention are generally directed to preventing adisplay unit from lighting up when a person only passes in front of animage forming apparatus, and to activating the image forming apparatusto shorten a wait time during which a user waits in front of the imageforming apparatus before starting job execution.

According to an aspect of the present invention, an image formingapparatus with a display unit includes a detection unit configured todetect a user of the image forming apparatus, a power supply controlunit configured to, when a person approaching the image formingapparatus is detected by the detection unit when the image formingapparatus is in a power saving state where power supply to a functionunit included in the image forming apparatus is stopped, activate thefunction unit while maintaining the display unit in a non-display state,and a display control unit configured to, when the user of the imageforming apparatus instructs the display unit to present display afterpower is supplied to the function unit by the power supply control unit,change the display unit to a display state.

Further features of the present disclosure will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an outer appearance of an image forming apparatusaccording to a first exemplary embodiment.

FIG. 2 is a hardware block diagram illustrating the image formingapparatus.

FIG. 3 is a block diagram illustrating power supply in the image formingapparatus.

FIG. 4 is a state transition diagram of the image forming apparatus.

FIG. 5 illustrates the image forming apparatus in a standby state.

FIG. 6 illustrates the image forming apparatus in a power saving state.

FIG. 7 illustrates the image forming apparatus in a silent return state.

FIG. 8 illustrates the image forming apparatus in a display unit returnstate.

FIGS. 9A, 9B, and 9C illustrate details of an operation unit.

FIG. 10 illustrates power control transition according to a distancebetween the image forming apparatus and a user.

FIG. 11 is a flowchart illustrating power control of the image formingapparatus.

FIG. 12 illustrates a state where the user brings the hand above theoperation unit of the image forming apparatus.

FIG. 13 is a hardware block diagram illustrating the operation unit ofan image forming apparatus according to a second exemplary embodiment.

FIG. 14 is a flowchart illustrating processing executed by amicrocomputer of the operation unit.

DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments will be described below with reference to theaccompanying drawings.

FIG. 1 illustrates an outer appearance of an image forming apparatus 100according to a first exemplary embodiment.

The image forming apparatus 100 is a multifunction peripheral (MFP)serving a plurality of functions, such as a print function, a scannerfunction, a copy function, and a facsimile function.

The image forming apparatus 100 is provided with an ultrasonic sensor 15for detecting a person approaching the image forming apparatus 100. Whenthe ultrasonic sensor 15 detects a person approaching the image formingapparatus 100, the image forming apparatus 100 returns from the powersaving state where the image forming apparatus 100 consumes smallerpower than in the standby state where any one of the above-describedfunctions is operative.

The ultrasonic sensor 15 outputs a 40-kHz pulse wave in the non-audiofrequency range, and receives a pulse wave reflected by an object. Theultrasonic sensor 15 measures a distance between the image formingapparatus 100 and the object based on a time period since the ultrasonicsensor 15 outputs the pulse wave until it receives the reflection wave.Although, in the above-described example, the ultrasonic sensor 15 isused, an infrared light-receiving sensor for receiving an infrared rayemitted from the human body may be used as long as the sensor can detecta person. Further, instead of the ultrasonic sensor 15, a capacitancesensor for measuring a distance between the sensor and a target objectbased on the capacitance between the sensor and the target object.Furthermore, instead of the ultrasonic sensor 15, an infrared arraysensor having infrared light-receiving elements arranged linearly or inmatrix form.

The ultrasonic sensor 15 has a detection area A1 having a fan shape. Todetect a person without receiving influence from obstacles, such as acomputer placed on a desk, the ultrasonic sensor 15 may be disposed sothat a pulse wave is output in the upward direction.

FIG. 2 is a hardware block diagram illustrating the image formingapparatus 100.

A controller 11 for controlling operations of the entire image formingapparatus 100 will be described below with reference to FIG. 2.

As illustrated in FIG. 2, the image forming apparatus 100 includes acontroller 11 for comprehensively controlling operations of the imageforming apparatus 100, an operation unit 12, a scanner unit 13, aprinter unit 14, and the ultrasonic sensor 15.

The controller 11 is connected with the operation unit 12, the scannerunit 13, and the printer unit 14 such that the controller 11 is able tocommunicate with each unit. The controller 11 includes a centralprocessing unit (CPU) 301, a random access memory (RAM) 302, a read onlymemory (ROM) 303, a power supply control unit 304, an input/outputinterface (I/F) 305, and a local area network (LAN) controller 306. TheCPU 301, the RAM 302, the ROM 303, the power supply control unit 304,the input/output I/F 305, and the LAN controller 306 are connected to asystem bus 307. The controller 11 further includes a hard disk drive(HDD) 308, an image processing unit 309, a scanner I/F 310, and aprinter I/F 311. The HDD 308, the image processing unit 309, the scannerI/F 310, and the printer I/F 311 are connected to an image bus 312.

The CPU 301 comprehensively controls access with various devicesconnected based on a control program stored in the ROM 303, and alsocomprehensively controls various processing performed by the controller11. The RAM 302 is a system work memory required for operations of theCPU 301. The RAM 302 also serves as a memory for temporarily storingimage data. The ROM 303 stores a boot program of the image formingapparatus 100.

The power supply control unit 304 controls power supply to each unit ofthe image forming apparatus 100. The power supply control unit 304 willbe described in detail below. The input/output I/F 305 is an interfaceunit for connecting the system bus 307 and the operation unit 12. Theinput/output I/F 305 receives image data to be displayed on theoperation unit 12 from the system bus 307, outputs the image data to theoperation unit 12, and outputs information input from the operation unit12 to the system bus 307. The LAN controller 306 transmits and receivesinformation to/from an external apparatus 20 connected to the network30.

The HDD 308 is a hard disk drive for storing system software and imagedata. The image processing unit 309 performs image processing. Morespecifically, the image processing unit 309 reads image data stored inthe RAM 302, and performs image processing, such as enlargement andreduction (for JPEG and JBIG) and color adjustment, on the image data.The scanner I/F 310 is an interface unit for communicating with ascanner control unit 331 of the scanner unit 13. The printer I/F 311 isan interface unit for communicating with a printer control unit 341 ofthe printer unit 14. The image bus 312 is a transmission line forexchanging image data, and is composed of a peripheral componentinterconnect (PCI) bus or IEEE 1394.

The scanner unit 13 optically reads an image on a document and generatesimage data. The scanner unit 13 includes the scanner control unit 331and a scanner driving unit 332. The scanner driving unit 332 includes adriving unit for moving a reading head for reading a document, and adriving unit for conveying a document to a reading position. The scannercontrol unit 331 controls operations of the scanner driving unit 332.The scanner control unit 331 receives setting information set by a userat the time of scanner processing through communication with the CPU301, and controls operations of the scanner driving unit 332 based onthe setting information.

The printer unit 14 forms an image on a recording medium (paper)according to the electrophotographic process. The printer unit 14includes the printer control unit 341 and a printer driving unit 342.The printer driving unit 342 includes motors for rotating photosensitivedrums (not illustrated), a mechanism for applying pressure to a fixingunit, and a heater. The printer control unit 341 controls operations ofthe printer driving unit 342. The printer control unit 341 receivessetting information set by a user at the time of printer processingthrough communication with the CPU 301, and controls operations of theprinter driving unit 342 based on the setting information.

FIG. 3 is a block diagram illustrating power supply in the image formingapparatus 100.

A power supply configuration of the image forming apparatus 100 will bedescribed below with reference to FIG. 3.

The image forming apparatus 100 includes a first power supply unit 501,a second power supply unit 502, and a third power supply unit 503. Thefirst power supply unit 501 generates direct current (DC) power of about5.0V from alternating current (AC) power supplied via a plug P. Thefirst power supply unit 501 supplies generated DC power to the LANcontroller 306, the RAM 302, the ultrasonic sensor 15, the CPU 301, theROM 303, and the HDD 308, as well as to a power saving button 204, amicrocomputer 203, a touch panel 206, and a display unit 201 of theoperation unit 12. Hereinafter, the devices which are supplied withpower from the first power supply unit 501 are referred to as firstpower supply system devices. The second power supply unit 502 generatesDC power of about 12.0V from AC power supplied via the plug P. Thesecond power supply unit 502 supplies generated DC power to thebacklight 207, the image processing unit 309, the printer control unit341, and the scanner control unit 331. Hereinafter, the devices whichare supplied with power from the second power supply unit 502 arereferred to as second power supply system devices. The third powersupply unit 503 generates DC power of about 24.0V from AC power suppliedvia the plug P. The third power supply unit 503 supplies generated DCpower to the printer driving unit 342 and the scanner driving unit 332.Hereinafter, the devices which are supplied with power from the thirdpower supply unit 503 are referred to as third power supply systemdevices.

A seesaw switch 510 is provided between the first power supply unit 501and the first power supply system devices. The seesaw switch 510 turnsON or OFF according to a user's operation. A relay switch 511 isprovided in parallel with the seesaw switch 510. The relay switch 511supplies power generated by the first power supply unit 501 to the firstpower supply system devices. Even when the seesaw switch 510 is turnedOFF by a user's operation, power is supplied from the first power supplyunit 501 to the first power supply system devices via the relay switch511. The power supply control unit 304 is notified that the seesawswitch 510 is turned OFF via the signal A. When the seesaw switch 510 isturned OFF, the power supply control unit 304 instructs the CPU 301 toexecute shutdown processing. Then, when the shutdown processing isexecuted by the CPU 301, the power supply control unit 304 turns therelay switch 511 OFF. Accordingly, the image forming apparatus 100 turnsOFF.

A relay switch 512 is provided between the plug P and the second powersupply unit 502. The relay switch 512 enables or disables power supplyfrom the plug P to the second power supply unit 502. A relay switch 513is provided between the plug P and the third power supply unit 503. Therelay switch 513 enables or disables power supply from the plug P to thethird power supply unit 503.

A switch 514 is provided between the first power supply unit 501, andthe CPU 301, the ROM 303, the HDD 308, the touch panel 206 and thedisplay unit 201. The switch 514 starts or stops power supply to the CPU301, the ROM 303, the HDD 308, the touch panel 206, and the display unit201. A switch 515 is provided between the scanner control unit 331 andthe second power supply unit 502. The switch 515 starts or stops powersupply to the scanner control unit 331. A switch 516 is provided betweenthe printer control unit 341 and the second power supply unit 502. Theswitch 516 starts or stops power supply to the printer control unit 341.

A switch 517 is provided between the second power supply unit 502 and abacklight 207 which lights up the display unit 201 of the operation unit12 to visualize screen display. The switch 517 starts or stops powersupply to the backlight 207.

A switch 518 is provided between the scanner driving unit 332 and thethird power supply unit 503. The switch 518 starts or stops power supplyto the scanner driving unit 332. A switch 519 is provided between theprinter driving unit 342 and the third power supply unit 503. The switch519 starts or stops power supply to the printer driving unit 342.

The power supply control unit 304 will be described in detail below.

The power supply control unit 304 is a programmable logic circuit as arewritable circuit. More specifically, the power supply control unit 304according to the present exemplary embodiment is a complex programmablelogic device (CPLD). Although, in the present exemplary embodiment, thepower supply control unit 304 includes a CPLD, the configuration is notlimited thereto. The power supply control unit 304 may be a processorsuch as a CPU, which executes the processing based on software.

The power supply control unit 304 detects a return factor for returningthe image forming apparatus 100 from a power saving state ST4. The powersupply control unit 304 performs power supply control according to thedetected return factor. The above-described return factor includes thefollowing events:

-   -   The seesaw switch 510 is turned ON from OFF.    -   A specific packet (for example, a print job) has been received        from the external apparatus 20.    -   A person has approached the image forming apparatus 100, and the        power saving button 204 has been pressed by a user. Signals A,        P, Q, and R indicating the above-described return factors are        input to the power supply control unit 304. The signal A        indicates the (ON/OFF) state of the seesaw switch 510. The        signal P indicates that the LAN controller 306 has received a        specific packet (for example, a print job) from the external        apparatus 20. The signal Q indicates that the ultrasonic sensor        15 detected an object such as a person. The signal R indicates        that the power saving button 204 of the operation unit 12 has        been pressed by a user.

The power supply control unit 304 outputs signals B, C, D, E, F, H, andI (controls the logic of the signal B, C, D, E, F, H, and I). The signalB turns the relay switch 511 ON or OFF. The signal C turns the relayswitches 512 and 513 ON or OFF. The signal D turns the switch 514 ON orOFF. The signal E turns the switch 515 ON or OFF. The signal F turns theswitch 516 ON or OFF. The signal H turns the switch 518 ON or OFF. Thesignal I turns the switch 519 ON or OFF.

When the seesaw switch 510 is turned OFF by a user's operation, thelogic of the signal A changes to the Lo level. When the logic of thesignal A changes to the Lo level, the power supply control unit 304instructs the CPU 301 to shut down the image forming apparatus 100. TheCPU 301 executes shutdown processing in response to the above-describedinstruction. The power supply control 340 controls the signals B and Cto turn OFF the relay switches 511, 512, and 513. Accordingly, the imageforming apparatus 100 can be appropriately turned OFF after the shutdownprocessing.

When the LAN controller 306 receives a specific packet (a print job)from the external apparatus 20, the logic of the signal P changes to theHi level. When the logic of the signal P changes to the Hi level, thepower supply control unit 304 controls the signals C, D, F, and I toturn ON the relay switches 512, 513, 514, 516, and 519. Accordingly, theprinter unit 14 performs printing based on the print job.

When the ultrasonic sensor 15 detects an object such as a person, thelogic of the signal Q changes to the Hi level. When the logic of thesignal Q changes to the Hi level, the power supply control unit 304controls the signals C, D, E, F, H, and I to turn ON the switches 512 to516, 518, and 519.

At this timing, the microcomputer 203 outputs an output signal G with alogic at the Lo level. The signal G can turn the switch 517 ON or OFF.When the logic of the signal G is at the Lo level, the switch 517 turnsOFF. Therefore, when the ultrasonic sensor 15 detects an object, theimage forming apparatus 100 returns from the power saving state ST4 in astate where power is not supplied to the backlight 207.

When the ultrasonic sensor 15 detects an object such as a person, thepower supply control unit 304 changes the logic of signals Y and X tothe Hi level.

The signal X is used to select whether the scanner control unit 331activates the scanner unit 13 together with the drive of the scannerdriving unit 332 or not together with the drive of the scanner drivingunit 332. If the logic of the signal X is at the Hi level when power issupplied to the scanner control unit 331, the scanner control unit 331activates the scanner unit 13 while suspending the drive of the scannerdriving unit 332 (hereinafter referred to as silent start of the scannerunit 13). If the logic of the signal X is at the Lo level when power issupplied to the scanner control unit 331, the scanner control unit 331activates the scanner unit 13 together with the drive of the scannerdriving unit 332.

The signal Y is used to select whether the printer control unit 341activates the printer unit 14 together with the drive of the printerdriving unit 342 or not together with the drive of the printer drivingunit 342. If the logic of the signal X is at the Hi level when power issupplied to the printer control unit 341, the printer control unit 341activates the printer unit 14 while suspending the drive of the printerdriving unit 342 (hereinafter referred to as silent start of the printerunit 14). If the logic of the signal X is at the Lo level when power issupplied to the printer control unit 341, the printer control unit 341activates the printer unit 14 together with the drive of the printerdriving unit 342.

When the user presses the power saving button 204, the logic of thesignal R changes to the Hi level. When the logic of the signal R changesto the Hi level, the power supply control unit 304 controls the signalsC to I to turn ON the relay switches 512 to 519. When the power savingbutton 204 is pressed, the power supply control unit 304 changes thelogic of the signals Y and X to the Hi level. When the power savingbutton 204 is pressed, the backlight 207 lights up unlike theabove-described case where the ultrasonic sensor 15 detects a person.

The above-described switches 511 to 519 may be semiconductor switches(for example, field effect transistors (FETs)) instead of mechanicalswitches.

FIG. 4 is a state transition diagram of the image forming apparatus 100.

A state transition of the image forming apparatus 100 will be describedbelow with reference to FIG. 4.

The image forming apparatus 100 assumes a standby state ST1, a displayunit return state ST2, a silent return state ST3, a power saving stateST4, and a power OFF state ST5.

The standby state ST1 is a state where a reading operation can beperformed by the scanner unit 13, and a printing operation can beperformed by the printer unit 14.

When the image forming apparatus 100 is not in use for a predeterminedperiod, for example, when the operation unit 12 is not operated for apredetermined period and no job is received from the external apparatus20 in the standby state ST1, a state of the image forming apparatus 100transitions from the standby state ST1 to the power saving state ST4. Inthe power saving state ST4, smaller power is consumed than in thestandby state ST1. In the power saving state ST4, power is supplied onlyto devices (the ultrasonic sensor 15, the LAN controller 306, etc.)which are required to return from the power saving state ST4.

When the ultrasonic sensor 15 detects a person in the power saving stateST4, the state of the image forming apparatus 100 transitions to thesilent return state ST3. In the silent return state ST3, the CPU 301,the image processing unit 309 and the HDD 308, of the controller 11, thescanner unit 13, and the printer unit 14 are activated. Both the printerunit 14 and the scanner unit 13 are silently driven. Therefore, theimage forming apparatus 100 silently starts. In the above-describedactivation process, the CPU 301, the image processing unit (applicationspecific integrated circuit (ASIC)) 309, the CPU of the scanner controlunit 331, and the CPU of the printer control unit 341 executeinitialization. When a print job is received in the power saving stateST4, in which the external apparatus 20 instructs the printer unit to doprinting, the state of the image forming apparatus 100 transitions tothe standby state ST1.

When the user presses the power saving button 204 or when the ultrasonicsensor 15 continuously detects a person within a close range in thepower saving state ST4, the state of the image forming apparatus 100transitions to the display unit return state ST2 (described below). Inthe present exemplary embodiment, since the user is supposed to bedetected by the ultrasonic sensor 15 before the power saving button 204is pressed, the power saving button 204 is not to be pressed in thepower saving state ST4.

When the user presses the power saving button 204 or when the ultrasonicsensor 15 continuously detects a person within a close range in thesilent return state ST3, the state of the image forming apparatus 100transitions to the display unit return state ST2 where the backlight 207is lighted up and the display unit 201 is displayed. Accordingly, theuser is able to select a function of the image forming apparatus 100 viaa main menu screen (selection screen) 201 a (refer to FIG. 9B) displayedon the display unit 201.

When the user selects a function of the image forming apparatus 100 viathe main menu screen 201 a displayed in the display unit return stateST2, the state of the image forming apparatus 100 transitions to thestandby state ST1 where the selected function can be executed. Forexample, when the user selects a print function via the main menu screen201 a, the drive of the printer driving unit 342 is started. Morespecifically, the pressing of the fixing unit, the heating of theheater, the drive of a polygon mirror, the rotation of various motors,etc. are started. When the user selects a scanner function via the mainmenu screen 201 a, the scanner driving unit 332 drives the scanner unit13. More specifically, a reading position adjustment operation of areading unit and the rotation of various motors are started.

When the seesaw switch 510 is turned OFF from ON by a user operation,the state of the image forming apparatus 100 transitions to the powerOFF state.

Each of the above-described states will be described in detail belowwith reference to FIGS. 5 to 8.

Referring to FIGS. 5 to 8, power is not supplied to shaded portions.

As illustrated in FIG. 5, in the standby state ST1, each of the switch510 to 519 of the image forming apparatus 100 is turned ON, and power issupplied to each unit of the image forming apparatus 100.

As illustrated in FIG. 6, in the power saving state ST4, power issupplied to some of the first power supply system devices. In the powersaving state ST4, the relay switch 511 for supplying power generated bythe first power supply unit 501 is turned ON, and other switches 512 to519 are turned OFF. Accordingly, in the power saving state ST4, power issupplied to the power supply control unit 304, the RAM 302, the LANcontroller 306, the ultrasonic sensor 15, the power saving button 204,and the microcomputer 203. Power may be supplied to the microcomputer203 when the ultrasonic sensor 15 detects a person.

As illustrated in FIG. 7, in the silent return state ST3, power issupplied to the display unit 201, the touch panel 206, the CPU 301, theHDD 308, the ROM 303, the image processing unit 309, the printer unit14, and the scanner unit 13 in addition to the devices supplied withpower in the power saving state ST4. The printer control unit 341 andthe scanner control unit 331 do not drive the printer driving unit 342and the scanner driving unit 332.

As illustrated in FIG. 8, in the display unit return state ST2, power issupplied to the backlight 207 in addition to the devices supplied withpower in the silent return state ST3. This state allows the user torecognize that the display unit 201 is displaying various types ofinformation.

FIGS. 9A, 9B, and 9C illustrate details of the operation unit 12.

As illustrated in FIG. 9A, the operation unit 12 includes the displayunit 201, buttons 202, and the microcomputer 203 (refer to FIG. 3).

The display unit 201 displays various types of images. Morespecifically, the microcomputer (display control unit) 203 displays onthe display unit 201 the main menu screen (selection screen) 201 a(refer to FIG. 9B) for selecting the copy function, the print function,the scan function, and other functions. The microcomputer 203 displayson the display unit 201 a setting screen 201 b (refer to FIG. 9C) forexecuting a function selected on the main menu screen 201 a. To allowthe user to see an image displayed on the display unit 201, themicrocomputer 203 lights up the backlight 207.

As illustrated in FIG. 9A, in the power OFF state ST5, the power savingstate ST4, and the silent return state ST3, no image is displayed on thedisplay unit 201 (non-display state). This non-display state may beeither a state where the backlight 207 is turned OFF although an imageto be displayed is drawn on the display unit 201 or a state where thedisplay unit 201 is turned OFF and no image is drawn on the display unit201. On the other hand, as illustrated in FIGS. 9B and 9C, a state wherea screen is displayed on the display unit is referred to as a displaystate.

As illustrated in FIG. 9B, the main menu screen 201 a includes a Copyicon 211 for executing the copy function, a Print icon 212 for executingthe print function, and a Scan icon 213 for executing the scannerfunction. The main menu screen 201 a further includes a Use Stored Fileicon 214 for using a file stored in the HDD 308, and a FAX icon 215 forexecuting the facsimile function. The main menu screen 201 a furtherincludes a Reception Tray icon 216 for checking received mails, and anInformation icon 217 for displaying various types of information.

As illustrated in FIG. 9C, the setting screen 201 b includes a Startbutton 218 for instructing the image forming apparatus 100 to execute aselected job (JOB B is selected in FIG. 9C).

The buttons 202 include a Start key 208 for the image forming apparatus100 to start the copy or the scan function. The buttons 202 furtherinclude a power saving button 204. If the user presses the power savingbutton 204 when the image forming apparatus 100 is in the standby stateST1, the state of the image forming apparatus 100 transitions to thepower saving state ST4. If the user presses the power saving button 204when the image forming apparatus 100 is in the power saving state ST4,the state of the image forming apparatus 100 transitions to the standbystate ST1. The buttons 202 further include a numeric keypad 205 forinputting the number of copies to be printed and other numeric values.

FIG. 10 illustrates power control transition according to the distancebetween the image forming apparatus 100 and the user. Referring to FIG.10, the drawings on the upper side illustrate distances between theimage forming apparatus 100 and the user, and the drawings on the lowerside illustrate power states of the image forming apparatus 100 when theuser is at respective positions illustrated on the upper side.

At a time T1, the user is out of the detection area A1 of the ultrasonicsensor 15, and the image forming apparatus 100 waits in the power savingstate ST4. In the power saving state ST4, power is supplied only tolimited devices such as the ultrasonic sensor 15. More specifically, inthe power saving state ST4, power is supplied to the LAN controller 306,the RAM 302, the ultrasonic sensor 15, the microcomputer 203, and thepower saving button 204.

At a time T2, the user enters the detection area A1 of the ultrasonicsensor 15, and the ultrasonic sensor detects the relevant user.Accordingly, power is supplied to the controller 11, etc. Morespecifically, at the time T2, power is supplied to the display unit 201,the touch panel 206, the scanner unit 13, the printer unit 14, the imageprocessing unit 309, the HDD 308, and the CPU 301 in addition to thedevices supplied with power in the power saving state ST4. Accordingly,the activation of the controller 11, the scanner unit 13, and theprinter unit 14 is started. However, the scanner control unit 331 doesnot start the drive of the scanner driving unit 332, and the printercontrol unit 341 does not start the drive of the printer driving unit342. Accordingly, the activation of the printer unit 14 and the scannerunit 13 is started without drive sound of the printer driving unit 342and the scanner driving unit 332.

In the present exemplary embodiment, at the time T2, it is unknownwhether the user intends to use the image forming apparatus 100, andtherefore power is not supplied to the backlight 207. However, at thetime T2, the power saving button 204 lights up or blinks to present to aperson who intends to use the image forming apparatus 100, a portionwhich should be operated next.

At a time T3, the user who has approached the image forming apparatus100 presses the power saving button 204 or operates the touch panel 206,and power is supplied to the backlight 207 and a screen is displayed onthe display unit 201. In the present exemplary embodiment, since theuser presses the power saving button 204 and the touch panel 206 to usethe image forming apparatus 100, power is supplied to the backlight 207when the user presses the power saving button 204 or the touch panel206. When the backlight 207 lights up, the display unit 201 displays themain menu screen 201 a for selecting a function (copy, print, scan, box,facsimile, etc.) of the image forming apparatus 100.

At a timing 14, the user selects a function on the main menu screen 201a, and power is supplied to portions required to execute the relevantfunction. The following describes a case where the user selects thePrint icon 212 displayed on the main menu screen 201 a. When the userselects the Print icon 212 on the main menu screen 201 a, the printercontrol unit 341 starts the drive of the printer driving unit 342.

FIG. 11 is a flowchart illustrating processing executed by themicrocomputer 203 of the operation unit 12. A series of operationsperformed by the image forming apparatus 100 to return to the standbystate ST1 from the power saving state ST4 will be described below withreference to FIG. 11. Each step of the flowchart illustrated in FIG. 11is implemented when the microcomputer 203 of the operation unit 12executes a relevant program.

The image forming apparatus 100 waits in the power saving state ST4.

In step S101, the microcomputer 203 determines whether a person hasentered the detection area A1 of the ultrasonic sensor 15. Morespecifically, upon reception of a signal (output when the ultrasonicsensor 15 detects a person) from the ultrasonic sensor 15, themicrocomputer 203 determines that a person has entered the detectionarea A1 of the ultrasonic sensor 15 (YES in step S101).

When the microcomputer 203 determines that a person has entered thedetection area A1 of the ultrasonic sensor 15 (YES in step S101), thenin step S102, the microcomputer 203 instructs the power supply controlunit 304 to supply power to the CPU 301, the HDD 308, the imageprocessing unit 309, the printer unit 14, and the scanner unit 13. Morespecifically, the signal Q changes to the Hi level. Upon reception ofthe above-described instruction, the power supply control unit 304controls the logic of the signals C, D, E, F, H, and I such that poweris supplied to the display unit 201, the CPU 301, the HDD 308, the imageprocessing unit 309, the printer unit 14, and the scanner unit 13. Thedisplay unit 201, the CPU 301, the HDD 308, the image processing unit309, the printer unit 14, and the scanner unit 13 start activation whensupplied with power. At this timing, power is not supplied to thebacklight 207, and therefore a screen is not displayed on the displayunit 201. At this timing, neither the printer driving unit 342 nor thescanner driving unit 332 is driven. Therefore, the above-describedactivation is not accompanied by drive sound of the printer driving unit342 and the scanner driving unit 332.

Then, in step S103 a, the microcomputer 203 determines whether the powersaving button 204 has been pressed, or in step S103 b, the microcomputer203 determines whether the ultrasonic sensor 15 continuously detects aperson at a close range. When a predetermined time period has elapsedwithout detecting the above-described events (YES in step S104), then instep S105, the microcomputer 203 instructs the power supply control unit304 to stop power supply to the CPU 301, the HDD 308, the imageprocessing unit 309, the printer unit 14, and the scanner unit 13. Uponreception of the above-described instruction, the power supply controlunit 304 controls the logic of the signals C, D, E, F, H, and I to stoppower supply to the CPU 301, the HDD 308, the image processing unit 309,the printer unit 14, and the scanner unit 13. Accordingly, the state ofthe image forming apparatus 100 transitions to the power saving stateST4.

On the other hand, when the microcomputer 203 determines that the userhas pressed the power saving button 204 or the touch panel 206 beforethe above-described predetermined time has elapsed (YES in step S103 a),then in step S106, the microcomputer 203 turns ON the backlight 207 todisplay the main menu screen 201 a on the display unit 201. Also whenthe microcomputer 203 determines that the ultrasonic sensor 15continuously detects a person at a close range (YES in step S103 b), instep S106, the microcomputer 203 turns ON the backlight 207 to displaythe main menu screen 201 a on the display unit 201. More specifically,the microcomputer 203 outputs the signal G with the logic at Hi level toturn ON the relay switch 517 to supply power to the backlight 207. Whenthe user selects the Copy icon 211 in the main menu screen 201 a (YES instep S107), then in step S108, the microcomputer 203 starts the drive ofthe printer driving unit 342 and the scanner driving unit 332 requiredto execute the copy function. Accordingly, the state of the imageforming apparatus 100 transitions to the standby state ST1 where thecopy function can be executed.

When the user selects the Print icon 212 in the main menu screen 201 a(YES in step S109), then in step S110, the microcomputer 203 starts thedrive of the printer driving unit 342 required to execute the printfunction. Accordingly, the state of the image forming apparatus 100transitions to the standby state ST1 where the print function can beexecuted.

When the user selects the Scan icon 213 in the main menu screen 201 a(YES in step S111), then in step S112, the microcomputer 203 starts thedrive of the scanner driving unit 332 required to execute the scanfunction. Accordingly, the state of the image forming apparatus 100transitions to the standby state ST1 where the scanner function can beexecuted.

While, in the above-described example, the Copy icon 211, the Print icon212, and the Scan icon 213 in the main menu screen 201 a are selected,the relevant processing also applies to a case where other icons areselected. When the other icons are selected, power is supplied to afunction unit (for example, the facsimile unit) required to execute thefunction corresponding to the selected icon. For example, when the userselects the FAX icon 215 in the main menu screen 201 a, power issupplied to the scanner unit 13 required to perform facsimiletransmission.

As described above, in the first exemplary embodiment, when theultrasonic sensor 15 detects a person, the microcomputer 203 activates adevice for executing a function of the image forming apparatus 100. Morespecifically, in the first exemplary embodiment, since device activationcan be started before the user determines a function to be used, deviceactivation is already completed when the user selects a function to beused. Therefore, the user is able to execute the selected functionwithout waiting for device activation.

Further, in the first exemplary embodiment, when the ultrasonic sensor15 detects a person, power is not supplied to the backlight 207 andtherefore the display unit 201 does not light up. For this reason, thedisplay unit 201 does not light up when a person only passes through theinside of the detection range A1 of the ultrasonic sensor 15.

Furthermore, in the first exemplary embodiment, when the ultrasonicsensor 15 detects a person, neither the scanner driving unit 332 nor theprinter driving unit 342 is driven and therefore drive sound can beprevented from being generated each time a person passes by.

FIG. 12 illustrates a state where the user brings the hand above thedisplay unit 201 of the image forming apparatus 100.

As illustrated in FIG. 12, the operation unit 12 includes a capacitancesensor for the touch panel 206. This capacitance sensor detects anapproach of a person according to the capacitance of a capacitor formedbetween the hand of the person approaching the operation unit 12 and thecapacitance sensor. When the person's hand enters a detection area A2 ofthe capacitance sensor, power is supplied to the backlight 207, and themain menu screen 201 a is displayed on the display unit 201.

FIG. 13 is a hardware block diagram illustrating the operation unit ofan image forming apparatus 100 according to a second exemplaryembodiment. The microcomputer 203 is connected to the ultrasonic sensor15, the touch panel 206, the backlight 207, and the buttons 202. Asignal Q is a detection signal of the ultrasonic sensor 15 which isoutput from the ultrasonic sensor 15 to the microcomputer 203. When aperson is detected within a predetermined range, an analog signal may beoutput from the ultrasonic sensor 15 through an amplifier or acomparator, or an analog signal may be directly input to themicrocomputer 203. The signal Q from the ultrasonic sensor 15 enablesthe microcomputer 203 to know the distance to a person. Upon detectionof a signal J, the microcomputer 203 determines that the Start key 208or the numeric keypad 205 has been pressed. When the Start key 208 orthe numeric keypad 205 is pressed, the signal J changes to the logic Lolevel. Upon reception of a signal K, the microcomputer 203 determinesthat the touch panel 206 has been touched and what position is detectedin 2-dimensional coordinates of the touch panel 206. When the usertouches the touch panel 206, the microcomputer 203 notifies the CPU 301of coordinate data of the touched position via a serial communicationline M. Then, the CPU 301 determines the coordinates of the touchedposition and transmits the following screen data corresponding to thetouch to the display unit 201 via a data signal L.

FIG. 14 is a flowchart illustrating processing executed by themicrocomputer 203 of the operation unit 12. The following describesoperations executed by the microcomputer 203 when the state of the imageforming apparatus 100 transitions to the silent return state ST3 and thedisplay unit return state ST2 from the power saving state ST4.

The microcomputer 203 has a plurality of operation modes (power states).In the power saving state ST4, the microcomputer 203 operates in a lowpower mode in which the microcomputer 203 only periodically polls theconnection signal Q from the ultrasonic sensor 15. The signal Q may be areflection wave signal output by the ultrasonic sensor 15 or aninterrupt signal output when the time interval until the reflection wavereturns is shorter than a threshold value preset in a circuit. In thepresent case, the signal Q is acquired by performing A/D conversion onthe reflection wave signal. In step S202, the microcomputer 203 pollsthe signal Q from the ultrasonic sensor 15 at intervals of 100milliseconds (ms). When the time interval indicates a preset distance orshorter, the microcomputer 203 returns the operation mode (power state)to the normal operation with the signal G turned OFF. In step S203, themicrocomputer 203 periodically checks whether the button 202 or thetouch panel 206 has been operated. When the button 202 or the touchpanel 206 has been operated (YES in step S203), then in step S204, themicrocomputer 203 cancels the operated button and panel coordinate. Thereason why the microcomputer 203 cancels the relevant information isthat the information is based not on a button or panel operationintentionally performed by the user to return from the sleep mode, buton an unintentional operation in a case a notification is made to theCPU 301. Immediately after that, in step S206, the microcomputer 203turns ON the signal G and then turns ON the backlight 207.

On the other hand, even when neither the button 202 nor the touch panel206 is operated (NO in step S203), in a case where the ultrasonic sensor15 continuously detects a person within a close range during a timeperiod of about 500 ms (YES in step S205), in step S206, themicrocomputer 203 turns ON the signal G and then turns ON the backlight207. When the button 202 or the touch panel 206 is operated afterturning ON the backlight 207 (YES in step S207), then in step S208, themicrocomputer 203 notifies the CPU 301 of the operated button and panelcoordinate. When neither the button 202 nor the touch panel 206 isoperated after turning ON the backlight 207, the microcomputer 203receives a low power mode shift instruction from the CPU 301 via theserial communication line M. When the instruction has been received (YESin step S209), then in step S210, the microcomputer 203 turns OFF thesignal G and then turns OFF the backlight 207. In step S211, the imageforming apparatus 100 changes the operation mode to the low power mode.

Although, in the present exemplary embodiment, the microcomputer 203cancels the button operated or the panel coordinate touched while thebacklight 207 is turned OFF, and then turns ON the backlight 207, theprocessing is not limited thereto. The microcomputer 203 may notify theCPU 301 of the operated button and panel coordinate and then the CPU 301may cancel them.

OTHER EMBODIMENTS

Although, in the first exemplary embodiment, the ultrasonic sensor 15 isused, a camera may be used instead of the ultrasonic sensor 15. Insteadof using a camera provided on the image forming apparatus 100, a camera(for example, a monitoring camera) provided in a room where the imageforming apparatus 100 is installed may be used.

Although, in the second exemplary embodiment, the main menu screen 201 ais displayed on the display unit 201 by using a capacitance sensor 250,a touch-panel sensor of the display unit 201 may be used instead of thecapacitance sensor 250.

Although the above-described exemplary embodiments are applied to animage forming apparatus, additional exemplary embodiments are applicableto various apparatuses, such as a (desktop or laptop) personal computer,a personal digital assistant (PDA), a mobile phone, a tablet, a smartphone, and a camera.

Further, the above-described processing in flowcharts can be executed byone processor or a plurality of processors operating in collaboration.

Functions described in flowcharts in the present exemplary embodimentcan be implemented by executing software (program) acquired via anetwork or various types of storage media with a processing unit (a CPUor a processor) such as a personal computer.

Additional embodiments can also be realized by a computer of a system orapparatus that reads out and executes computer executable instructionsrecorded on a storage medium (e.g., computer-readable storage medium) toperform the functions of one or more of the above-describedembodiment(s), and by a method performed by the computer of the systemor apparatus by, for example, reading out and executing the computerexecutable instructions from the storage medium to perform the functionsof one or more of the above-described embodiment(s). The computer maycomprise one or more of a central processing unit (CPU), microprocessing unit (MPU), or other circuitry, and may include a network ofseparate computers or separate computer processors. The computerexecutable instructions may be provided to the computer, for example,from a network or the storage medium. The storage medium may include,for example, one or more of a hard disk, a random-access memory (RAM), aread only memory (ROM), a storage of distributed computing systems, anoptical disk (such as a compact disc (CD), digital versatile disc (DVD),or Blu-ray Disc (BD)™), a flash memory device, a memory card, and thelike.

While the present disclosure has been described with reference toexemplary embodiments, it is to be understood that these exemplaryembodiments are not seen to be limiting. The scope of the followingclaims is to be accorded the broadest interpretation so as to encompassall such modifications and equivalent structures and functions.

What is claimed is:
 1. A printing apparatus comprising: a device; adisplay unit which displays an image; a user operation detection unitwhich detects a user operation to the display unit; a human detectionunit which detects a human; and a power control unit which turns on thedevice based on a detection result of the human detection unit and turnson the display unit based on a detection result of the user operationdetection unit, wherein the display unit is not turned on based on thedetection result of the human detection unit.
 2. The printing apparatusaccording to claim 1, further comprising a motor, wherein the motor isnot driven on based on a detection result of the human detection unit.3. The printing apparatus according to claim 1, wherein the display unitdisplays a predetermined screen based on the detection result of theuser operation detection unit.
 4. The printing apparatus according toclaim 3, further comprising a print unit which prints image on a medium,wherein a predetermined device of the print unit is driven based on adetection result of the user operation detection unit.
 5. The printingapparatus according to claim 4, wherein the predetermined device of theprinting unit is driven before a print instruction to execute printingis received.
 6. The printing apparatus according to claim 4, wherein thepredetermined device of the printing unit is not driven based on adetection result of the human detection unit.
 7. The printing apparatusaccording to claim 4, wherein the predetermined device of the printer isa fixing unit.
 8. The printing apparatus according to claim 4, whereinthe predetermined device of the printer is a heater.
 9. The printingapparatus according to claim 4, wherein the predetermined device of theprinter is a polygon mirror.
 10. The printing apparatus according toclaim 4, wherein the predetermined device of the printer is a motor. 11.The printing apparatus according to claim 4, wherein the predetermineddevice of the print unit is driven based on the detection result that auser operation for a predetermined button on the predetermined screen isdetected.
 12. The printing apparatus according to claim 11, wherein thepredetermined screen is a menu screen including at least a copy buttonfor executing a copy function and a scan button for executing a scanfunction, and wherein the predetermined button is the copy button. 13.The printing apparatus according to claim 1, wherein the device is a CPUor a HDD.
 14. The printing apparatus according to claim 1, wherein thedisplay unit includes a backlight, and turning on the display unitcomprises lighting up the backlight.
 15. The printing apparatusaccording to claim 1, wherein the human detection unit is an ultrasonicsensor.
 16. The printing apparatus according to claim 1, wherein thehuman detection unit is an infrared sensor.
 17. The printing apparatusaccording to claim 1, wherein the human detection unit is a capacitancesensor.
 18. The printing apparatus according to claim 1, wherein thehuman detection unit is a camera.
 19. The printing apparatus accordingto claim 1, wherein the human detection unit detects a human approachingthe printing apparatus.
 20. The printing apparatus according to claim 1,wherein the user operation detection unit is a touch sensor.
 21. Amethod of turning on a device of a printing apparatus comprising:detecting a human; detecting a user operation to a display unit; turningon the device based on the detecting the human without turning on adisplay unit which display an image; and turning on the display unitbased on the detecting the user operation to the display unit.
 22. Themethod according to claim 21, wherein a motor of the printing apparatusis not driven on based on the detecting the human.
 23. The methodaccording to claim 21, further comprising; driving a predetermineddevice of a print unit which prints image on a medium based on detectinga user operation to the display unit.
 24. The method according to claim21, wherein the device is a CPU or a HDD.
 25. A printing apparatuscomprising: a display unit which display an image; a user operationdetection unit which detects a user operation to the display unit; ahuman detection unit which detects a human; and a power state shift unitwhich shifts a power state of the printing apparatus from a first powerstate to a second power state higher power consumption than the firstpower state based on a detection result of the human detection unit andshifts the power state of the printing apparatus from the second powerstate to a third power state higher power consumption than the secondpower state based on a detection result of the user operation detectionunit, wherein the display unit is not turned on based on the detectionresult of the human detection unit.
 26. The printing apparatus accordingto claim 25, further comprising a motor, wherein the motor is not drivenon based on a detection result of the human detection unit.
 27. Theprinting apparatus according to claim 25, further comprising a displayunit which displays a predetermined screen based on the detection resultof the user operation detection unit.
 28. The printing apparatusaccording to claim 27, further comprising a print unit which printsimage on a medium, wherein a predetermined device of the print unit isdriven based on a detection result of the user operation detection unit.29. The printing apparatus according to claim 28, wherein thepredetermined device of the printing unit is driven before a printinstruction to execute printing is received.
 30. The printing apparatusaccording to claim 28, wherein the predetermined device of the printingunit is not driven based on a detection result of the human detectionunit.
 31. The printing apparatus according to claim 28, wherein thepredetermined device of the printer is a fixing unit.
 32. The printingapparatus according to claim 28, wherein the predetermined device of theprinter is a heater.
 33. The printing apparatus according to claim 28,wherein the predetermined device of the printer is a polygon mirror. 34.The printing apparatus according to claim 28, wherein the predetermineddevice of the printer is a motor.
 35. The printing apparatus accordingto claim 28, wherein the predetermined device of the print unit isdriven based on the detection result that a user operation for apredetermined button on the predetermined screen is detected.
 36. Theprinting apparatus according to claim 35, wherein the predeterminedscreen is a menu screen including at least a copy button for executing acopy function and a scan button for executing a scan function, andwherein the predetermined button is the copy button.
 37. The printingapparatus according to claim 25, wherein the device is a CPU or a HDD.38. The printing apparatus according to claim 25, wherein the displayunit includes a backlight, and turning on the display unit compriseslighting up the backlight.
 39. The printing apparatus according to claim25, wherein the human detection unit is an ultrasonic sensor.
 40. Theprinting apparatus according to claim 25, wherein the human detectionunit is an infrared sensor.
 41. The printing apparatus according toclaim 25, wherein the human detection unit is a capacitance sensor. 42.The printing apparatus according to claim 25, wherein the humandetection unit is a camera.
 43. The printing apparatus according toclaim 25, wherein the human detection unit detects a human approachingthe printing apparatus.
 44. The printing apparatus according to claim25, wherein the user operation detection unit is a touch sensor.
 45. Amethod of turning on a device of a printing apparatus comprising:detecting a human; detecting a user operation to a display unit;shifting a power state of the printing apparatus from a first powerstate to a second power state higher power consumption than the firstpower state based on the detecting the human without turning on adisplay unit which displays an image; and shifting the power state ofthe printing apparatus from the second power state to a third powerstate higher power consumption than the second power state based on thedetecting the user operation to the display unit.
 46. The methodaccording to claim 45, wherein a motor of the printing apparatus is notdriven on based on the detecting the human.
 47. The method according toclaim 45, further comprising; driving a predetermined device of a printunit which prints image on a medium based on detecting a user operationto the display unit.
 48. The method according to claim 45, wherein thedevice is a CPU or a HDD.